libata: implement PMP helpers
Implement helpers to test whether PMP is supported, attached and
determine pmp number to use when issuing SRST to a link. While at it,
move ata_is_host_link() so that it's together with the two new PMP
helpers.
This change simplifies LLDs and helps making PMP support optional.
Signed-off-by: Tejun Heo <htejun@gmail.com>
diff --git a/include/linux/libata.h b/include/linux/libata.h
index eb86d6f..1908bf48 100644
--- a/include/linux/libata.h
+++ b/include/linux/libata.h
@@ -1090,13 +1090,38 @@
.change_queue_depth = ata_scsi_change_queue_depth
/*
+ * PMP helpers
+ */
+static inline bool sata_pmp_supported(struct ata_port *ap)
+{
+ return ap->flags & ATA_FLAG_PMP;
+}
+
+static inline bool sata_pmp_attached(struct ata_port *ap)
+{
+ return ap->nr_pmp_links != 0;
+}
+
+static inline int ata_is_host_link(const struct ata_link *link)
+{
+ return link == &link->ap->link;
+}
+
+static inline int sata_srst_pmp(struct ata_link *link)
+{
+ if (sata_pmp_supported(link->ap) && ata_is_host_link(link))
+ return SATA_PMP_CTRL_PORT;
+ return link->pmp;
+}
+
+/*
* printk helpers
*/
#define ata_port_printk(ap, lv, fmt, args...) \
printk("%sata%u: "fmt, lv, (ap)->print_id , ##args)
#define ata_link_printk(link, lv, fmt, args...) do { \
- if ((link)->ap->nr_pmp_links) \
+ if (sata_pmp_attached((link)->ap)) \
printk("%sata%u.%02u: "fmt, lv, (link)->ap->print_id, \
(link)->pmp , ##args); \
else \
@@ -1182,11 +1207,6 @@
/*
* link helpers
*/
-static inline int ata_is_host_link(const struct ata_link *link)
-{
- return link == &link->ap->link;
-}
-
static inline int ata_link_max_devices(const struct ata_link *link)
{
if (ata_is_host_link(link) && link->ap->flags & ATA_FLAG_SLAVE_POSS)
@@ -1201,7 +1221,7 @@
static inline struct ata_link *ata_port_first_link(struct ata_port *ap)
{
- if (ap->nr_pmp_links)
+ if (sata_pmp_attached(ap))
return ap->pmp_link;
return &ap->link;
}
@@ -1210,8 +1230,8 @@
{
struct ata_port *ap = link->ap;
- if (link == &ap->link) {
- if (!ap->nr_pmp_links)
+ if (ata_is_host_link(link)) {
+ if (!sata_pmp_attached(ap))
return NULL;
return ap->pmp_link;
}